In the United States alone, over 45,000 women die each year from breast cancer and over 100,000 people from lung cancer (1). Tens of thousands more die from other types of cancer. One of the few plant derived drugs that has shown quantitative proof of cancer treatment is Taxol. Taxol has been shown to be effective over a wide range of the most deadly forms of cancer, such as ovarian, lung and breast (2).
Over the last 30 years, the pharmaceutical industry has spent vast sums of money in an attempt to synthesize Taxol. Their efforts have not been successful nor have their results proven cost effective to-date even considering the many public relations announcements to the contrary.
Taxol is currently very expensive, approximately $6,000 per treatment (3). The reason for this is the short supply of raw material needed to manufacture the drug and the inability of research scientists to mass synthesize the drug.
Currently, the approved NCI-accepted method of Taxol production is from the bark of the Pacific Yew (4). This crude method requires approximately 10,000 pounds of biomass to produce approximately one pound of Taxol (5). This environmentally insensitive method of obtaining biomass for Taxol extraction is the current state-of-the-art now being employed.
With a "return to nature" trend taking hold and the desire by some people to seek plant related drugs for human ailments, another non-synthetic technology approach to the Taxol availability problem is possible.
As a result of the gross limitations discussed above, the inventors of this patent have developed a unique and commercial process to overcome the shortage of biomass needed for the extraction of Taxol. The plant growth system of the present invention incorporates two key components:
1. The present invention uses a widely grown commercially available plant variety Taxus x media "Hicksii". By substituting this variety for the Pacific Yew one can eliminate the need to cut and destroy the rare Pacific Yew from its natural environment which could lead to the elimination of this rare species.
2. The present invention relates to the development of a new technique that the inventors have coined as "Compressed Dormancy" and is employed to cycle the plant from a non-growing condition to an active growing condition a number of times during a typical growing season. This ability to cycle the plant from "on" to "off", produces up to five (5) times as much growth annually as that produced in a normal annual growing season. This method provides for an increase in the amount of biomass produced which is then harvested and processed into useful products, such as Taxol.
This is a unique commercial process for increasing the number of growth cycles of plants as the inventors have demonstrated on a type of Taxol bearing plant. The methodology is based on the desire of the inventors to produce large amounts of biomass suitable for the extraction of Taxol, and ultimately for the low cost treatment of cancer.